I took the bolt from the rear caliper off and stopped in Sport authority yesterday figuring they carry a full line of Diamond back. They said they'll need to replace the caliper, that they don't have spare parts.

However, I found that almost all of the disk brakes there use that same bolth with a matching thread. The easiest way would have been to pocket one of those little suckers, but I guess that's not right. This morning i will try the hardware store.